LONDON — Theresa May won backing from MPs to renegotiate her Brexit deal with the EU — but faced an instant rejection from Brussels.

The House of Commons voted by 317 votes to 301 in favor of an amendment requiring the most controversial aspect of the Brexit deal — the Irish backstop proposal for avoiding a hard border on the island of Ireland — to be replaced by “alternative arrangements.”

In response to the votes in Westminster, the EU27 swiftly squashed any hope of a renegotiation of the Brexit withdrawal treaty without a more substantive revision of the U.K. red lines.

“This is our position, as coordinated with EU27 capitals,” a spokesman for European Council President Donald Tusk said immediately after the votes.

“We welcome and share the U.K. parliament's ambition to avoid a no-deal scenario,” the spokesman, Preben Aamann, said. “We continue to urge the U.K. government to clarify its intentions with respect to its next steps as soon as possible.”

“If she comes with the same position as before she will get the same answer" — Senior European Commission official

But he added: “The Withdrawal Agreement is and remains the best and only way to ensure an orderly withdrawal of the United Kingdom from the European Union. The backstop is part of the Withdrawal Agreement, and the Withdrawal Agreement is not open for renegotiation. The December European Council conclusions are very clear on this point.”

In the statement, Tusk's spokesman stressed the EU’s long-standing willingness to rework the withdrawal treaty if the U.K. were to fundamentally shift its positions on what it seeks in a future relationship. The EU has long said that London’s red lines make only a free-trade agreement possible, while under a different framework the U.K. could remain in the EU’s single market, its customs union or both.

“If the U.K.'s intentions for the future partnership were to evolve, the EU would be prepared to reconsider its offer and adjust the content and the level of ambition of the political declaration, whilst respecting its established principles,” Aamann said.

The EU also expressed willingness to extend the March 29 deadline for the U.K.’s withdrawal.

Yvette Cooper, the Labour MP whose amendment was voted down in the House of Commons | Leon Neal/Getty Images

“Should there be a U.K. reasoned request for an extension, the EU27 would stand ready to consider it and decide by unanimity,” he said. “The EU27 will adopt this decision, taking into account the reasons for and duration of a possible extension, as well as the need to ensure the functioning of the EU institutions. We will continue our preparations for all outcomes, including a no-deal scenario. We will also continue the EU's process of ratification of the agreement reached with the U.K. government. President Tusk will stay in close contact with EU27 leaders.”

Earlier on Tuesday, a senior European Commission official said that if May returns to Brussels with nothing new, she would find herself flatly rebuffed.

“If she comes with the same position as before,” the official said, “she will get the same answer.”

MPs also rejected a plan, backed by opposition parties, that would have given the House of Commons the opportunity to delay Brexit. However, they did back a non-binding amendment rejecting the prospect of a no-deal Brexit.

A proposal put down by Labour MP Yvette Cooper that aimed to force the government to delay Brexit day was backed by 298 MPs with 321 voting against — a deficit of 23.

The amendment, which was opposed by the government, would have carved out parliamentary time for legislation requiring the government to ask for an extension to Article 50 if no Brexit deal is approved by MPs by February 26. All EU27 leaders would have had to agree unanimously to such an extension.

May’s government has pledged to bring back the vote on the deal “as soon as possible” but has not set a date.

MPs did vote for an amendment to simply "reject" the U.K. leaving the EU without a deal. The amendment from former Conservative minister Caroline Spelman was backed by 318 MPs with 310 against — a majority of eight. The vote is non-binding, so does not rule out no-deal and there is no obligation for the government to act.

Following the votes, May said the results have shown there is a majority of MPs who “would support a deal with changes to the backstop,” adding that she would now “seek to obtain legally binding changes to the Withdrawal Agreement.”

However, at a meeting before the votes were held, Brexiteer MPs made clear that their endorsement of the backstop amendment — put forward by senior backbencher Graham Brady — does not necessarily mean they would back May’s deal when it returns for a second attempt at a ratification vote.

May’s government has pledged to bring back the vote on the deal “as soon as possible” but has not set a date. If no deal has been reached by February 13, MPs will be given another opportunity to debate Brexit the following day.

Responding to the results, Labour leader Jeremy Corbyn said he would meet May to discuss the way forward — an option he had rejected when her deal was defeated earlier this month.